Improvement in revolving stereoscopes



[com y N. FEYERS, FHOTO-LITHOGRAPHER. WASHINGTON. D. C.

fwwww NER, WASHINGTON u c sind Gettin.

ALEXANDER BECKERS, OF NEW YORK, N. Y.

Letters Patent N 99,135, dated January 25, 1870.

IMPROVEMENT IN REVOLVING- STEREOSCOPES.

The Schedule referred to in these Letters Patent and making part of the same.

To allwhom. it 'may concern Be it known that I, ALEXANDER Bnoxnns, of the city `and State of New York, have invented and made a new and useful Improvement in Stcrcoscopes; and

,I do hereby declare the following to be a full, clear,

Figure 4 is a detached section at the turning-lmob.'

Similar letters of reference denote the same parts.

The object of this invention is to simplify the construction. of the chain for the pictures, also to support said chain on a swinging frame, so that the picture may be brought to a focus with facility, and avoid the complicated mechanism heretofore employed.

I also 'fit the lens at one of the. fronts of the camera, so that it can be slid up or down, and when down, open a space for allowing light to pass in ibi' transparent pictures.

In the drawingl o. (t are the sides, and

11 and c, the fronts ofthe stcreoscope-box.

The frame for the chain of stereoscopes, is formed of two side-pieces d e, united firmly together by the cross-piece f, that is framed into d and e, and properly secured so that the entire frame can b e swung within the box; 2 being the screws that attach the lower ends of d and e to the inner surfaces of the sidepieces a a.

At the upper ends of the side-pieces d c, is the shaft t', for the chain, the same projecting at one end through an elongated openingiu the box a; and r/ is the revolving knob, and l1., a rose or flange to4 cover the elongated opening in a.

By this constructi0n,'thc frame d cf can be swung on the 'screws 2, so as to focus the picture.

The shaft It forms the lower axis for the belt of pictures. This axis is fitted to slide in the frame d c, and the belt is strained by the springs 3. v

The belt of pictures is made of wooden strips n n, glued to and iirmly att-ached upon the belt of canvas, or similar material, that passes around the polygonal axes or shafts Ii and It.

Instead of having wooden frames, as heretofore usual, I make the picture-holder of a wire, o, bent up into an oblong shape, and the bent ends pass into the ends of the strips n., as shown by dotted lines, and a sheet metal clasp, m, is provided to hold the edge of the picture, as in lny patent of Marcil 29, 1866.

'lhe lens p is placed eccentric tothe opening in the .eye-tube, in order to obtain the necessaryretraction of the light from the pictures, to show but one picture.

I make use of the septa rr rl, to cut off the rays of light. and confine the vision to the picture. It is, however, to be understood that where the picture is moved, so as to bring it to focus, the stationary septum, as ordinarily employed, would allow portions of the second picture to be seen on the margin, thus marring the effect. ',lto prevent this, I introducea movable septum, r, between the lenses andthe adjustable picture, and the same is moved simultaneously with the picture.

I have shown this septum as supported bya spring, r2, inside the box, and moved by small side-levers 20, having projections 2l near the middle, to take the edges of the septum and links 22, from the lower ends of the levers 20, connect them with the upper part of the swinging frame d c, so that the sept-um will be moved, as the frame d c is moved to adjust the picturc, but only about half the distanoefthus adjusting said septum, so as always to cut off the rays ot hght from outside the picture.

The links 22 have bends in them, so as to facilitate the proper positioning of the parts in applying thc septum, by bending said links more or less.

Stereoscopes have been made with a hinged front, that turns down when glass or transparent pictures are to beshown. In this case, the inner sides of the lenses become dust-y, and the camera-box is unflo bremedy these objections, l make use of a front, c?, that is fitted to slide vertically down into the base c, the front heilig set in grooves at 5 5. n

. I also provide a sliding glass, s, that is set 1n a light metal frame, so as to be moved up and down in' the slide-nays 6 (i, and the lever t is connected at its ends by the links fnand t', (sce dotted lines, iig, 3,) with the sliding front c2, and glass, s, respectively, so that as the iront is sliddcn down, the glass is raised, and the reverse.

The swinging lids w are made with concave under, s urfaces, so that when turned up, they illuminate the pictures, the surfaces being silvered or covered with bright reflecting foil that concentrates the rays of light.

Ihat I claim, and desire to secure by Letters Patent, is-

1. ',lhe swinging frame for the chain of photographic pictures, formed of the side-pieces de, and cross-piece, f, firmly united together, said frame being attached by the screws or pins 2, and moved by the knob y, as set forth.

The front c?, carrying a pair of lenses, in co'mbin'ation with the glass s, lever t, and grooves in the stereoscope-box, substantially as setfort-h, so that the front and glass can be simultaneously moved in opposite directions, as specified.

3. A septum applied between the picture and the lens, and moved automatically and simultaneously with the picture, so as to adjust said septum the proper proportionate distance, as aud'for the purposes set forth.

In witness whereof, I have hereunto set my signature, this 24th'day ot' March, 1869.

Witnesses: ALEX. BEOKERS.

OHAs. H. SMITH, GEO. T. PINOKNEY. 

